On 27 March 1940 George Orwell, or Eric Blair if you prefer, found it was "still impossible to sow seeds", but applied wood-ash to his onion bed, noted that the tadpoles were almost fully formed and beginning to wriggle their tails, and sold 20 eggs for 2s 10d. That is all. Didn't he know there was a war on?

Of course, he knew perfectly well that there was; his concentration on the domestic is one indication that hostilities had not reached the point where one could think about little else. The war diaries begin in earnest detail on 28 May, with the Belgian capitulation and retreat of the British Expeditionary Force to Dunkirk.

Much in here will be familiar to those who have thoroughly read Orwell's oeuvre. The hop-picking diary is reworked for sections of Down and Out in Paris and London; we have the embryo for The Road to Wigan Pier; the Morocco diary was reworked for his piece "Marrakech"; and the wartime diaries were purposefully written with an eye towards eventual publication.

But that doesn't even begin to make the Diaries redundant, or otiose. In fact, not only do you not have to be an Orwell nut in order to enjoy them: they can be read by anyone who is interested in daily life between 1931 and 1949. There are gaps: the diaries between March 1936 and September 1938 were confiscated by the NKVD and are probably still gathering dust somewhere in their archives; and bomb damage, inter alia, did for the second half of the war. But this leaves us plenty to be going on with. Orwell was a meticulous observer of the ordinary as well as the extraordinary, and there is something pleasing in the fact that he is aware not only of the larger picture (with a few hostages to fortune: in 1940, he wrote: "When you see how the wealthy are still behaving, in what is manifestly developing into a revolutionary war, you think of St Petersburg in 1916." Revolutionary? Well, perhaps, but only if you stretch the definition somewhat) but also of the minutiae of housekeeping. You can actually learn something about gardening, as well as keeping hens and goats; Orwell was a devoted and assiduous smallholder. One of the minor pleasures of the book are the reproductions of Orwell's own sketches of the lathes used by carpenters in Morocco, the stirrups used by Arab horsemen and charcoal braziers – "the charcoal can be started with very little paper & wood & smoulders for hours". Why is this so pleasing? I suppose it is because it makes Orwell, already one of the most human and intimate of writers, even more vivid for us. It is as if we are with him.

The prose is largely without ornamentation, and unrefined, but this doesn't make it dull. There are occasional raw moments – "that bastard Chiappe is cold meat . . . this war is at any rate killing off a few fascists" – but considering what we are reading is, in effect, his notes and first drafts, the result is highly readable, and it becomes plain that Orwell couldn't have written an inelegant or ineffective sentence if he tried. It's also worth noting Peter Davison's exemplary editorial work. Not only does he do a first-rate job of intercalating (a word I do not think I had hitherto come across, and for which I am very grateful) various diaries to produce a seamless chronological narrative, but he leaves in some of Orwell's misspellings (there is something comforting in knowing that he wasn't perfect), and annotates everything that needs to be annotated. If he errs on the side of inclusiveness, then so much the better. Foreign readers, after all, may not know that John Lewis is "a leading department store, organised as a staff partnership, which still thrives", and the detail about the staff partnership is, in its way, a little nod to the kind of principles which Orwell favoured. And if there is something compulsive about Davison's dedication, then this is entirely of a piece with the subject matter.

That we can now read these diaries is a cause for celebration. The extraordinary thing is that we had to wait so long for them in the first place. Well, here they are at last.